This invention relates generally to medical devices and more particularly to obturators.
Access to the vascular or other systems within the body of a living being are now being provided by many types of minimally invasive devices, such as needles, sheath introducers, catheters, etc. Often the procedure involved in providing access to the interior of the being's body requires the maintenance of the access device's lumen in position, e.g., within the interior of an artery, while providing a secure closure at the proximal fitting of the device, e.g., to prevent the egress of blood therefrom. In order to effect that secure closure, conventional devices, such as obturators, have been used in the access device's lumen. Such obturators typically comprise an elongated, rod-like element which when extended into the lumen of the access device protrude slightly beyond its distal (open) end. The obturator is held in place in the lumen via an appropriate fitting cooperating with a fitting on the access device. In order to facilitate the placement of the obturator within the access device, the obturator is typically formed of a relatively rigid material so that its tip is rigid or hard. Thus, when such a prior art obturator is used it may traumatize the tissue which is engaged by the rigid tip, particularly if the obturator is left in place (indwells) for an extended period of time.
Conventional obturators have included radiopaque materials therein, e.g., barium sulfate, in order to enable the user to radiographically image the device to determine its placement within the body. As will be appreciated by those skilled in the art the inclusion of a radiopaque material, such as barium sulfate, into an obturator material, such as polyurethane, has the effect of reducing its tensile strength (while coincidentally increasing the hardness somewhat). This factor has limited the concentration of such radiopaque materials in prior art obturators to relatively low levels, e.g., 12 percent by weight in obturators of Teflon and 20 percent by weight in obturators of polyurethane, in order to maintain structural integrity. However, by using such a relatively low concentration of radiopaque material the radiographic image produced is less than optimum.
Thus, a need exists for an obturator which does not pose a potential tissue traumatization hazard, even if left in place for an extended period of time, and whose location within the body can be readily determined utilizing radiographic imaging.